s390/hmcdrv: HMC drive CD/DVD access (8f933b10) · Commits · e / devices / android_kernel_oneplus_sm7250

arch/s390/include/asm/irq.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -51,6 +51,7 @@ enum interruption_class {
		IRQEXT_CMS,
		IRQEXT_CMC,
		IRQEXT_CMR,
		IRQEXT_FTP,
		IRQIO_CIO,
		IRQIO_QAI,
		IRQIO_DAS,

arch/s390/kernel/irq.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,7 @@ static const struct irq_class irqclass_sub_desc[NR_ARCH_IRQS] = {
		{.irq = IRQEXT_CMS, .name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling"},
		{.irq = IRQEXT_CMC, .name = "CMC", .desc = "[EXT] CPU-Measurement: Counter"},
		{.irq = IRQEXT_CMR, .name = "CMR", .desc = "[EXT] CPU-Measurement: RI"},
		{.irq = IRQEXT_FTP, .name = "FTP", .desc = "[EXT] HMC FTP Service"},
		{.irq = IRQIO_CIO, .name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt"},
		{.irq = IRQIO_QAI, .name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt"},
		{.irq = IRQIO_DAS, .name = "DAS", .desc = "[I/O] DASD"},

drivers/s390/char/Kconfig

+13 −0

Original line number	Diff line number	Diff line
		@@ -102,6 +102,19 @@ config SCLP_ASYNC
		want for inform other people about your kernel panics,
		need this feature and intend to run your kernel in LPAR.

		config HMC_DRV
		def_tristate m
		prompt "Support for file transfers from HMC drive CD/DVD-ROM"
		depends on 64BIT
		select CRC16
		help
		This option enables support for file transfers from a Hardware
		Management Console (HMC) drive CD/DVD-ROM. It is available as a
		module, called 'hmcdrv', and also as kernel built-in. There is one
		optional parameter for this module: cachesize=N, which modifies the
		transfer cache size from it's default value 0.5MB to N bytes. If N
		is zero, then no caching is performed.

		config S390_TAPE
		def_tristate m
		prompt "S/390 tape device support"

drivers/s390/char/Makefile

+3 −0

Original line number	Diff line number	Diff line
		@@ -33,3 +33,6 @@ obj-$(CONFIG_S390_VMUR) += vmur.o

		zcore_mod-objs := sclp_sdias.o zcore.o
		obj-$(CONFIG_CRASH_DUMP) += zcore_mod.o

		hmcdrv-objs := hmcdrv_mod.o hmcdrv_dev.o hmcdrv_ftp.o hmcdrv_cache.o diag_ftp.o sclp_ftp.o
		obj-$(CONFIG_HMC_DRV) += hmcdrv.o

drivers/s390/char/diag_ftp.c

0 → 100644

+237 −0

Original line number	Diff line number	Diff line
		/*
		* DIAGNOSE X'2C4' instruction based HMC FTP services, useable on z/VM
		*
		* Copyright IBM Corp. 2013
		* Author(s): Ralf Hoppe (rhoppe@de.ibm.com)
		*
		*/

		#define KMSG_COMPONENT "hmcdrv"
		#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

		#include <linux/kernel.h>
		#include <linux/mm.h>
		#include <linux/irq.h>
		#include <linux/wait.h>
		#include <linux/string.h>
		#include <asm/ctl_reg.h>

		#include "hmcdrv_ftp.h"
		#include "diag_ftp.h"

		/* DIAGNOSE X'2C4' return codes in Ry */
		#define DIAG_FTP_RET_OK 0 /* HMC FTP started successfully */
		#define DIAG_FTP_RET_EBUSY 4 /* HMC FTP service currently busy */
		#define DIAG_FTP_RET_EIO 8 /* HMC FTP service I/O error */
		/* and an artificial extension */
		#define DIAG_FTP_RET_EPERM 2 /* HMC FTP service privilege error */

		/* FTP service status codes (after INTR at guest real location 133) */
		#define DIAG_FTP_STAT_OK 0U /* request completed successfully */
		#define DIAG_FTP_STAT_PGCC 4U /* program check condition */
		#define DIAG_FTP_STAT_PGIOE 8U /* paging I/O error */
		#define DIAG_FTP_STAT_TIMEOUT 12U /* timeout */
		#define DIAG_FTP_STAT_EBASE 16U /* base of error codes from SCLP */
		#define DIAG_FTP_STAT_LDFAIL (DIAG_FTP_STAT_EBASE + 1U) /* failed */
		#define DIAG_FTP_STAT_LDNPERM (DIAG_FTP_STAT_EBASE + 2U) /* not allowed */
		#define DIAG_FTP_STAT_LDRUNS (DIAG_FTP_STAT_EBASE + 3U) /* runs */
		#define DIAG_FTP_STAT_LDNRUNS (DIAG_FTP_STAT_EBASE + 4U) /* not runs */

		/**
		* struct diag_ftp_ldfpl - load file FTP parameter list (LDFPL)
		* @bufaddr: real buffer address (at 4k boundary)
		* @buflen: length of buffer
		* @offset: dir/file offset
		* @intparm: interruption parameter (unused)
		* @transferred: bytes transferred
		* @fsize: file size, filled on GET
		* @failaddr: failing address
		* @spare: padding
		* @fident: file name - ASCII
		*/
		struct diag_ftp_ldfpl {
		u64 bufaddr;
		u64 buflen;
		u64 offset;
		u64 intparm;
		u64 transferred;
		u64 fsize;
		u64 failaddr;
		u64 spare;
		u8 fident[HMCDRV_FTP_FIDENT_MAX];
		} __packed;

		static DECLARE_COMPLETION(diag_ftp_rx_complete);
		static int diag_ftp_subcode;

		/**
		* diag_ftp_handler() - FTP services IRQ handler
		* @extirq: external interrupt (sub-) code
		* @param32: 32-bit interruption parameter from &struct diag_ftp_ldfpl
		* @param64: unused (for 64-bit interrupt parameters)
		*/
		static void diag_ftp_handler(struct ext_code extirq,
		unsigned int param32,
		unsigned long param64)
		{
		if ((extirq.subcode >> 8) != 8)
		return; /* not a FTP services sub-code */

		inc_irq_stat(IRQEXT_FTP);
		diag_ftp_subcode = extirq.subcode & 0xffU;
		complete(&diag_ftp_rx_complete);
		}

		/**
		* diag_ftp_2c4() - DIAGNOSE X'2C4' service call
		* @fpl: pointer to prepared LDFPL
		* @cmd: FTP command to be executed
		*
		* Performs a DIAGNOSE X'2C4' call with (input/output) FTP parameter list
		* @fpl and FTP function code @cmd. In case of an error the function does
		* nothing and returns an (negative) error code.
		*
		* Notes:
		* 1. This function only initiates a transfer, so the caller must wait
		* for completion (asynchronous execution).
		* 2. The FTP parameter list @fpl must be aligned to a double-word boundary.
		* 3. fpl->bufaddr must be a real address, 4k aligned
		*/
		static int diag_ftp_2c4(struct diag_ftp_ldfpl *fpl,
		enum hmcdrv_ftp_cmdid cmd)
		{
		int rc;

		asm volatile(
		" diag %[addr],%[cmd],0x2c4\n"
		"0: j 2f\n"
		"1: la %[rc],%[err]\n"
		"2:\n"
		EX_TABLE(0b, 1b)
		: [rc] "=d" (rc), "+m" (*fpl)
		: [cmd] "0" (cmd), [addr] "d" (virt_to_phys(fpl)),
		[err] "i" (DIAG_FTP_RET_EPERM)
		: "cc");

		switch (rc) {
		case DIAG_FTP_RET_OK:
		return 0;
		case DIAG_FTP_RET_EBUSY:
		return -EBUSY;
		case DIAG_FTP_RET_EPERM:
		return -EPERM;
		case DIAG_FTP_RET_EIO:
		default:
		return -EIO;
		}
		}

		/**
		* diag_ftp_cmd() - executes a DIAG X'2C4' FTP command, targeting a HMC
		* @ftp: pointer to FTP command specification
		* @fsize: return of file size (or NULL if undesirable)
		*
		* Attention: Notice that this function is not reentrant - so the caller
		* must ensure locking.
		*
		* Return: number of bytes read/written or a (negative) error code
		*/
		ssize_t diag_ftp_cmd(const struct hmcdrv_ftp_cmdspec ftp, size_t fsize)
		{
		struct diag_ftp_ldfpl *ldfpl;
		ssize_t len;
		#ifdef DEBUG
		unsigned long start_jiffies;

		pr_debug("starting DIAG X'2C4' on '%s', requesting %zd bytes\n",
		ftp->fname, ftp->len);
		start_jiffies = jiffies;
		#endif
		init_completion(&diag_ftp_rx_complete);

		ldfpl = (void *) get_zeroed_page(GFP_KERNEL \| GFP_DMA);
		if (!ldfpl) {
		len = -ENOMEM;
		goto out;
		}

		len = strlcpy(ldfpl->fident, ftp->fname, sizeof(ldfpl->fident));
		if (len >= HMCDRV_FTP_FIDENT_MAX) {
		len = -EINVAL;
		goto out_free;
		}

		ldfpl->transferred = 0;
		ldfpl->fsize = 0;
		ldfpl->offset = ftp->ofs;
		ldfpl->buflen = ftp->len;
		ldfpl->bufaddr = virt_to_phys(ftp->buf);

		len = diag_ftp_2c4(ldfpl, ftp->id);
		if (len)
		goto out_free;

		/*
		* There is no way to cancel the running diag X'2C4', the code
		* needs to wait unconditionally until the transfer is complete.
		*/
		wait_for_completion(&diag_ftp_rx_complete);

		#ifdef DEBUG
		pr_debug("completed DIAG X'2C4' after %lu ms\n",
		(jiffies - start_jiffies) * 1000 / HZ);
		pr_debug("status of DIAG X'2C4' is %u, with %lld/%lld bytes\n",
		diag_ftp_subcode, ldfpl->transferred, ldfpl->fsize);
		#endif

		switch (diag_ftp_subcode) {
		case DIAG_FTP_STAT_OK: /* success */
		len = ldfpl->transferred;
		if (fsize)
		*fsize = ldfpl->fsize;
		break;
		case DIAG_FTP_STAT_LDNPERM:
		len = -EPERM;
		break;
		case DIAG_FTP_STAT_LDRUNS:
		len = -EBUSY;
		break;
		case DIAG_FTP_STAT_LDFAIL:
		len = -ENOENT; /* no such file or media */
		break;
		default:
		len = -EIO;
		break;
		}

		out_free:
		free_page((unsigned long) ldfpl);
		out:
		return len;
		}

		/**
		* diag_ftp_startup() - startup of FTP services, when running on z/VM
		*
		* Return: 0 on success, else an (negative) error code
		*/
		int diag_ftp_startup(void)
		{
		int rc;

		rc = register_external_irq(EXT_IRQ_CP_SERVICE, diag_ftp_handler);
		if (rc)
		return rc;

		ctl_set_bit(0, 63 - 22);
		return 0;
		}

		/**
		* diag_ftp_shutdown() - shutdown of FTP services, when running on z/VM
		*/
		void diag_ftp_shutdown(void)
		{
		ctl_clear_bit(0, 63 - 22);
		unregister_external_irq(EXT_IRQ_CP_SERVICE, diag_ftp_handler);
		}